The transport and storage of large loads is a particular challenge to the transport, respectively storage, industry. This is even more so if the loads due to their extension and/or non-uniformity do not fit into any packaging system such as containers and/or if the loads are particularly heavy, i.e. above the weight that can be carried by normally-sized lorries.
An example of such large and very heavy loads are large components of wind turbines such as tower segments, rotor blades and nacelles. All of them have a substantial weight and do not fit into regularly-sized standard containers. In effect they are transported openly, i.e. their principal shape is visible during transport. For the purpose of illustration, in the following reference is only made to wind turbine nacelles, bearing in mind that this invention is also particularly useful for the other wind turbine components mentioned and indeed for other similarly bulky loads as well.
A wind turbine nacelle is typically installed on a transport and storage frame structure on which the nacelle rests stably. Such frame structure according to the state of the art is depicted in FIG. 1: A wind turbine nacelle 1 with a bottom opening 3 is loaded onto a frame structure 9 comprising a longitudinal frame 5 and two cross beams 7 to which the longitudunal frame 5 is connected fixedly. The nacelle 1 is removably fixed on the frame structure 9 in the region of the bottom opening 3 in a stable way, i.e. its point of gravity 2 is positioned such with respect to the frame structure 9 that no forward and backward and also no sideward movement of the nacelle 1 is to be expected. Additionally, the nacelle can be bolted to the frame structure 9 to add stability. When assembled, the opening 3 serves as an inlet for the tower (not shown) of the wind turbine.
According to the state of the art, the nacelle 1 together with the frame structure 9 is loaded on a loading device 11 which is shaped like a trough having an inner longitudinal extension d1 of approximately 7 meters and an outer longitudinal extension d2 of approximately 8.9 meters.
To transport such construction comprising the nacelle 1, the frame structure and the loading device 11 on a local site such as a fabrication yard, a harbour area or when loading (respectively off-loading) it, e.g. on so-called roll-off-roll-on (ro-ro) boats, normally a transport crane is necessary. Such crane lifts the complete load from the ground onto e.g. a trailer or a lorry (before transport) or down therefrom (after transport, e.g. for further transport or installment). The use of such cranes is time-consuming and necessitates special equipment and extreme care during loading.
In WO 2008/000267 A1 there is disclosed a nacelle with raising means attached to it. Once lifted, the nacelle can be lowered onto a transport plane of a means of transport. That implies, however, that each nacelle must be equipped with such raising means and/or must comprise areas in which the raising means can be attached. This has the effect that such system is quite expensive and requires some extra equipment.